Date of Award


Degree Name

Biological Sciences


College of Science

Type of Degree


Document Type


First Advisor

Guo-Zhang Zhu

Second Advisor

Nadja Spitzer

Third Advisor

David Mallory


Paracrine factor Desert hedgehog (Dhh) is essential for mouse spermatogenesis. However, the specific receptor of Dhh during spermatogenesis is unknown. This study aims to test the hypothesis that Ptchd3, a male germ cell-specific gene acts as a receptor for Dhh in spermatogenesis. In this study, a transgenic mouse model with Ptchd3 gene deletion was first successfully established. Then, in vivo fertility assay and in vitro analysis were performed on Ptchd3 null mutant male mice. The data obtained from the in vivo fertility experiments indicates that there is no statistical significance in offspring litter number (p-value 0.7973) and litter size (p-value 0.3648) among mutant, heterozygote and wild-type male mice. The data of in vitro sperm assay reveals that the abnormality /normality ratio of sperm morphology in Ptchd3 null mice demonstrates no statistical difference with that in wild-type mice (Tukey test interval ±4.7 to ±12.8). Taken together, these findings clearly attest that Ptchd3 is not essential for mouse spermatogenesis and fertility. However, whether Ptchd3 functions as a Dhh receptor remains undetermined. The knowledge gained from this research into the function of Ptchd3 on spermatogenesis could give us a better understanding of the Dhh signaling pathway in testis.


Spermiogenesis in animals.